The present invention pertains to an underground pipe installer device, and more particularly to a structural arrangement to secure the underground pipe installer within an operating trench prior to the pipe installing operation.
It is routine procedure in underground pipe installing operations to provide an operating trench on one side of a street or driveway, for example, under which a pipe is to be installed, and a target trench on the opposite side thereof. An underground pipe installer device is positioned and secured in the operating trench. A first push rod length is manually inserted in drive jaws of the device and operably engaged thereby to push the first rod length into the ground toward the target trench, generally by a fluid operated cylinder and piston assembly. The trailing end of the first rod length is provided with a coupling to receive a leading end of a second rod length, and the drive means is actuated to drive the second rod length forwardly toward the target trench. A subsequent plurality of rod lengths are successively interconnected in a like manner and driven forwardly until a leading tip end of the first rod length emerges into the target trench.
The leading tip end is threadedly provided with a pusher cap which is removed and replaced with a hole spreaded attachment which is attached to an end of a pipe to be permanently installed under the above surface in the hole thusby formed. For this purpose, means are provided to reverse the direction of movement of the rod assembly to pull the pipe attached thereto backwardly through the hole, formed by the rod assembly, until the leading end of the pipe emerges into the operating trench.
The above described operations are quite conventional, however, it is essential to anchor the pipe installer device securely in the operating trench against the very substantial reaction forces of the rod pushing operation so as to maintain a sufficient space behind the installer device to accomplish the manual rod coupling and uncoupling operations during the hole forming operation and in withdrawing the pipe into the hole.
It has been a general practice to brace the installer device against the rear end wall of the operating trench during the rod pushing operation, the bracing structure was then removed and reinstalled to engage against the front trench wall for the pipe pulling operation. Examples of brace means of this type are disclosed in Applicant's U.S. Pat. Nos. 3,907,253, 3,988,003 and 3,988,004.
Therefore, one of the principal objects of the present invention is to provide a pair of elongated abutment members in a parallel arrangement outwardly of respective sides of an underground pipe installer device, and connection means from the pair of abutment members to the main power source to utilize the very substantial power forces thereof to firmly engage the abutment members against respective side walls of the operating trench in a manner whereby the rod pushing and pipe pulling operations are accomplished without dislocating the pipe installer device.
A further object of the invention is to provide link means connecting between the abutment members and the push rod in a manner so as to utilize the forces of the main power source as said forces are being applied to the push rod in a forward direction.
Another object of the invention is to provide means to releasably lock the link means with the abutment members securely engaged against the side walls.